This invention relates generally to shifters for automotive transmissions and, more particularly, is directed to a drop-in type automotive transmission shifter which is spring biased into the neutral position with one or more flat springs.
Drop-in type shifters are well-known in the prior art. These shifters normally comprise a shift stick means for pivotally mounting the shift stick about a base, and a gear actuating lever which extends from the bottom of the base and into the transmission for changing the drive ratio of the transmission when the shift stick is manually pivoted. Often the means for pivotally mounting the shift stick comprises a ball and socket connection. The shifter is normally secured to the top of a transmission with bolts entering through the base of the shifter. The base is usually bolted over an aperture in the top of the transmission and the shift lever extends downwardly from the base through the aperture into the transmission. Hence, these types of shifters have been referred to as drop-in type shifters.
It has often been considered desirable to spring bias an automotive transmission shifter into a neutral position or neutral plane. In the case of a conventional manual automotive transmission having an H-shaped shift pattern implemented with a shift stick which is pivotable about first and second orthogonal axes, it has also been thought to be desirable to provide a differential spring bias which may, for example, be used to inhibit positioning the shifter in one or more gear positions such as the reverse gear position. Prior art attempts at achieving the aforementioned spring biasing characteristics in drop-in type shifters have employed the use of a plurality of coil-type springs for spring biasing the shifter. The coil springs are used to suspend a pair of yokes which encompass opposing ends of a rocking shaft that extends through the ball and socket of the shifter. These springs act in tension and compression to spring bias the shifter in an upright position and may be provided with different spring constants to effect a differential spring bias. The disadvantage of this prior art approach to spring biasing a drop-in type shifter is related to the expense of manufacturing such a shifter. Not only are the components somewhat expensive, but assembly techniques have proven to be time consuming.